The Measurement of Spray Quality for Pan Coating Processes

Abstract

In this study, we describe the use of an innovative imaging system to measure and control the effect of nozzle operating parameters on the characteristics of a spray. These characteristics, including spray pattern, droplet size distribution, and droplet velocity, define the quality of the spray. They can have significant impact on the efficiency of the pan coating process and the quality of the coat. Suspensions of different composition were used in this study, and the authors demonstrated that the spray characteristics can be controlled with this approach. The main conclusions from this study were: Spray characterization can be a powerful tool for exploring and establishing the design space of nozzles operation in the pan coating process. When scaling or transferring a spray coating process, the focus should be on maintaining consistent spray qualities rather than limiting nozzle operating parameters to a range. This approach embraces the FDA concept of process analytical technology (PAT) and design space (FDA, Guidance for industry PAT—A framework for innovative pharmaceutical development, manufacturing, and quality assurance, 2004) for science-based operation flexibility.